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                  <a href="#gstreamer-GstIterator.description" class="shortcut">Description</a></span>
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<a name="gstreamer-GstIterator"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle"><a name="gstreamer-GstIterator.top_of_page"></a>GstIterator</span></h2>
<p>GstIterator — Object to retrieve multiple elements in a threadsafe
way.</p>
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<div class="refsect1">
<a name="gstreamer-GstIterator.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorCopyFunction" title="GstIteratorCopyFunction ()">*GstIteratorCopyFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorNextFunction" title="GstIteratorNextFunction ()">*GstIteratorNextFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem"><span class="returnvalue">GstIteratorItem</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()">*GstIteratorItemFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorResyncFunction" title="GstIteratorResyncFunction ()">*GstIteratorResyncFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorFreeFunction" title="GstIteratorFreeFunction ()">*GstIteratorFreeFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorForeachFunction" title="GstIteratorForeachFunction ()">*GstIteratorForeachFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="gstreamer-GstIterator.html#GstIteratorFoldFunction" title="GstIteratorFoldFunction ()">*GstIteratorFoldFunction</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR:CAPS" title="GST_ITERATOR()">GST_ITERATOR</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-LOCK:CAPS" title="GST_ITERATOR_LOCK()">GST_ITERATOR_LOCK</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-COOKIE:CAPS" title="GST_ITERATOR_COOKIE()">GST_ITERATOR_COOKIE</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ORIG-COOKIE:CAPS" title="GST_ITERATOR_ORIG_COOKIE()">GST_ITERATOR_ORIG_COOKIE</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-new" title="gst_iterator_new ()">gst_iterator_new</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-new-list" title="gst_iterator_new_list ()">gst_iterator_new_list</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-new-single" title="gst_iterator_new_single ()">gst_iterator_new_single</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-copy" title="gst_iterator_copy ()">gst_iterator_copy</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-free" title="gst_iterator_free ()">gst_iterator_free</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()">gst_iterator_next</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()">gst_iterator_resync</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-push" title="gst_iterator_push ()">gst_iterator_push</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-filter" title="gst_iterator_filter ()">gst_iterator_filter</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()">gst_iterator_fold</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()">gst_iterator_foreach</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-find-custom" title="gst_iterator_find_custom ()">gst_iterator_find_custom</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody>
<tr>
<td class="datatype_keyword">struct</td>
<td class="function_name"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator">GstIterator</a></td>
</tr>
<tr>
<td class="datatype_keyword">enum</td>
<td class="function_name"><a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem">GstIteratorItem</a></td>
</tr>
<tr>
<td class="datatype_keyword">enum</td>
<td class="function_name"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult">GstIteratorResult</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;gst/gst.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.description"></a><h2>Description</h2>
<p>A GstIterator is used to retrieve multiple objects from another object in
a threadsafe way.</p>
<p>Various GStreamer objects provide access to their internal structures using
an iterator.</p>
<p>Note that if calling a GstIterator function results in your code receiving
a refcounted object (with, say, <a href="/usr/share/gtk-doc/html/gobject/gobject-Standard-Parameter-and-Value-Types.html#g-value-get-object"><code class="function">g_value_get_object()</code></a>), the refcount for that
object will not be increased. Your code is responsible for taking a reference
if it wants to continue using it later.</p>
<p>The basic use pattern of an iterator is as follows:</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
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12
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23
24</pre></td>
        <td class="listing_code"><pre class="programlisting">GstIterator <span class="gtkdoc opt">*</span>it <span class="gtkdoc opt">=</span> <span class="function">_get_iterator</span><span class="gtkdoc opt">(</span>object<span class="gtkdoc opt">);</span>
GValue item <span class="gtkdoc opt">=</span> G_VALUE_INIT<span class="gtkdoc opt">;</span>
done <span class="gtkdoc opt">=</span> FALSE<span class="gtkdoc opt">;</span>
<span class="keyword">while</span> <span class="gtkdoc opt">(!</span>done<span class="gtkdoc opt">) {</span>
  <span class="keyword">switch</span> <span class="gtkdoc opt">(</span><span class="function"><a href="gstreamer-GstIterator.html#gst-iterator-next">gst_iterator_next</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">, &amp;</span>item<span class="gtkdoc opt">)) {</span>
    <span class="keyword">case</span> GST_ITERATOR_OK<span class="gtkdoc opt">:</span>
      <span class="gtkdoc opt">...</span>get<span class="gtkdoc opt">/</span>use<span class="gtkdoc opt">/</span>change item here<span class="gtkdoc opt">...</span>
      <span class="function"><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#g-value-reset">g_value_reset</a></span> <span class="gtkdoc opt">(&amp;</span>item<span class="gtkdoc opt">);</span>
      <span class="keyword">break</span><span class="gtkdoc opt">;</span>
    <span class="keyword">case</span> GST_ITERATOR_RESYNC<span class="gtkdoc opt">:</span>
      <span class="gtkdoc opt">...</span>rollback changes to items<span class="gtkdoc opt">...</span>
      <span class="function"><a href="gstreamer-GstIterator.html#gst-iterator-resync">gst_iterator_resync</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">);</span>
      <span class="keyword">break</span><span class="gtkdoc opt">;</span>
    <span class="keyword">case</span> GST_ITERATOR_ERROR<span class="gtkdoc opt">:</span>
      <span class="gtkdoc opt">...</span>wrong parameters were given<span class="gtkdoc opt">...</span>
      done <span class="gtkdoc opt">=</span> TRUE<span class="gtkdoc opt">;</span>
      <span class="keyword">break</span><span class="gtkdoc opt">;</span>
    <span class="keyword">case</span> GST_ITERATOR_DONE<span class="gtkdoc opt">:</span>
      done <span class="gtkdoc opt">=</span> TRUE<span class="gtkdoc opt">;</span>
      <span class="keyword">break</span><span class="gtkdoc opt">;</span>
  <span class="gtkdoc opt">}</span>
<span class="gtkdoc opt">}</span>
<span class="function"><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#g-value-unset">g_value_unset</a></span> <span class="gtkdoc opt">(&amp;</span>item<span class="gtkdoc opt">);</span>
<span class="function"><a href="gstreamer-GstIterator.html#gst-iterator-free">gst_iterator_free</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p></p>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="GstIteratorCopyFunction"></a><h3>GstIteratorCopyFunction ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*GstIteratorCopyFunction<span class="c_punctuation">)</span> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                            <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *copy</code></em>);</pre>
<p>This function will be called when creating a copy of <em class="parameter"><code>it</code></em>
 and should
create a copy of all custom iterator fields or increase their
reference counts.</p>
<div class="refsect3">
<a name="GstIteratorCopyFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The original iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>copy</p></td>
<td class="parameter_description"><p>The copied iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorNextFunction"></a><h3>GstIteratorNextFunction ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
<span class="c_punctuation">(</span>*GstIteratorNextFunction<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                            <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *result</code></em>);</pre>
<p>The function that will be called when the next element of the iterator
should be retrieved.</p>
<p>Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this
function and pass it to the constructor of the custom iterator.
The function will be called with the iterator lock held.</p>
<div class="refsect3">
<a name="GstIteratorNextFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>result</p></td>
<td class="parameter_description"><p>a pointer to hold the next item</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="GstIteratorNextFunction.returns"></a><h4>Returns</h4>
<p> the result of the operation.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorItemFunction"></a><h3>GstIteratorItemFunction ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem"><span class="returnvalue">GstIteratorItem</span></a>
<span class="c_punctuation">(</span>*GstIteratorItemFunction<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                            <em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *item</code></em>);</pre>
<p>The function that will be called after the next item of the iterator
has been retrieved. This function can be used to skip items or stop
the iterator.</p>
<p>The function will be called with the iterator lock held.</p>
<div class="refsect3">
<a name="GstIteratorItemFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>item</p></td>
<td class="parameter_description"><p>the item being retrieved.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="GstIteratorItemFunction.returns"></a><h4>Returns</h4>
<p> the result of the operation.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorResyncFunction"></a><h3>GstIteratorResyncFunction ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*GstIteratorResyncFunction<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre>
<p>This function will be called whenever a concurrent update happened
to the iterated datastructure. The implementor of the iterator should
restart the iterator from the beginning and clean up any state it might
have.</p>
<p>Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this
function and pass it to the constructor of the custom iterator.
The function will be called with the iterator lock held.</p>
<div class="refsect3">
<a name="GstIteratorResyncFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorFreeFunction"></a><h3>GstIteratorFreeFunction ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*GstIteratorFreeFunction<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre>
<p>This function will be called when the iterator is freed.</p>
<p>Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this
function and pass it to the constructor of the custom iterator.
The function will be called with the iterator lock held.</p>
<div class="refsect3">
<a name="GstIteratorFreeFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorForeachFunction"></a><h3>GstIteratorForeachFunction ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*GstIteratorForeachFunction<span class="c_punctuation">)</span> (<em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *item</code></em>,
                               <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre>
<p>A function that is called by <a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()"><code class="function">gst_iterator_foreach()</code></a> for every element.</p>
<div class="refsect3">
<a name="GstIteratorForeachFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>item</p></td>
<td class="parameter_description"><p>The item</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>User data</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorFoldFunction"></a><h3>GstIteratorFoldFunction ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
<span class="c_punctuation">(</span>*GstIteratorFoldFunction<span class="c_punctuation">)</span> (<em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *item</code></em>,
                            <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *ret</code></em>,
                            <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre>
<p>A function to be passed to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a>.</p>
<div class="refsect3">
<a name="GstIteratorFoldFunction.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>item</p></td>
<td class="parameter_description"><p>the item to fold</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>ret</p></td>
<td class="parameter_description"><p>a <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> collecting the result</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>data passed to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="GstIteratorFoldFunction.returns"></a><h4>Returns</h4>
<p> <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the fold should continue, <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> if it should stop.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-ITERATOR:CAPS"></a><h3>GST_ITERATOR()</h3>
<pre class="programlisting">#define GST_ITERATOR(it)                ((GstIterator*)(it))
</pre>
<p>Macro to cast to a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a></p>
<div class="refsect3">
<a name="GST-ITERATOR.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> value</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-ITERATOR-LOCK:CAPS"></a><h3>GST_ITERATOR_LOCK()</h3>
<pre class="programlisting">#define GST_ITERATOR_LOCK(it)           (GST_ITERATOR(it)-&gt;lock)
</pre>
<p>Macro to get the lock protecting the datastructure being iterated.</p>
<div class="refsect3">
<a name="GST-ITERATOR-LOCK.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the lock of</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-ITERATOR-COOKIE:CAPS"></a><h3>GST_ITERATOR_COOKIE()</h3>
<pre class="programlisting">#define GST_ITERATOR_COOKIE(it)         (GST_ITERATOR(it)-&gt;cookie)
</pre>
<p>Macro to get the cookie of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>. The cookie of the
iterator is the value of the master cookie when the iterator
was created.
Whenever the iterator is iterated, the value is compared to the
value of the master cookie. If they are different, a concurrent
modification happened to the iterator and a resync is needed.</p>
<div class="refsect3">
<a name="GST-ITERATOR-COOKIE.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the cookie of</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-ITERATOR-ORIG-COOKIE:CAPS"></a><h3>GST_ITERATOR_ORIG_COOKIE()</h3>
<pre class="programlisting">#define GST_ITERATOR_ORIG_COOKIE(it)    (GST_ITERATOR(it)-&gt;master_cookie)
</pre>
<p>Macro to get a pointer to where the master cookie is stored. The
master cookie protects the structure being iterated and gets updated
whenever the datastructure changes.</p>
<div class="refsect3">
<a name="GST-ITERATOR-ORIG-COOKIE.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the master cookie of</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-new"></a><h3>gst_iterator_new ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
gst_iterator_new (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a> size</code></em>,
                  <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>,
                  <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>,
                  <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> *master_cookie</code></em>,
                  <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorCopyFunction" title="GstIteratorCopyFunction ()"><span class="type">GstIteratorCopyFunction</span></a> copy</code></em>,
                  <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorNextFunction" title="GstIteratorNextFunction ()"><span class="type">GstIteratorNextFunction</span></a> next</code></em>,
                  <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>,
                  <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorResyncFunction" title="GstIteratorResyncFunction ()"><span class="type">GstIteratorResyncFunction</span></a> resync</code></em>,
                  <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFreeFunction" title="GstIteratorFreeFunction ()"><span class="type">GstIteratorFreeFunction</span></a> free</code></em>);</pre>
<p>Create a new iterator. This function is mainly used for objects
implementing the next/resync/free function to iterate a data structure.</p>
<p>For each item retrieved, the <em class="parameter"><code>item</code></em>
 function is called with the lock
held. The <em class="parameter"><code>free</code></em>
 function is called when the iterator is freed.</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="gst-iterator-new.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>size</p></td>
<td class="parameter_description"><p>the size of the iterator structure</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>type</p></td>
<td class="parameter_description"><p><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of children</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>lock</p></td>
<td class="parameter_description"><p>pointer to a <a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"><span class="type">GMutex</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>master_cookie</p></td>
<td class="parameter_description"><p>pointer to a guint32 that is changed when the items in the
iterator changed.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>copy</p></td>
<td class="parameter_description"><p>copy function</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>next</p></td>
<td class="parameter_description"><p>function to get next item</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>item</p></td>
<td class="parameter_description"><p>function to call on each item retrieved</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>resync</p></td>
<td class="parameter_description"><p>function to resync the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>free</p></td>
<td class="parameter_description"><p>function to free the iterator</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-new.returns"></a><h4>Returns</h4>
<p> the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>.</p>
<p>MT safe.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-new-list"></a><h3>gst_iterator_new_list ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
gst_iterator_new_list (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>,
                       <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>,
                       <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint32"><span class="type">guint32</span></a> *master_cookie</code></em>,
                       <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Doubly-Linked-Lists.html#GList"><span class="type">GList</span></a> **list</code></em>,
                       <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject-struct"><span class="type">GObject</span></a> *owner</code></em>,
                       <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>);</pre>
<p>Create a new iterator designed for iterating <em class="parameter"><code>list</code></em>
.</p>
<p>The list you iterate is usually part of a data structure <em class="parameter"><code>owner</code></em>
 and is
protected with <em class="parameter"><code>lock</code></em>
.</p>
<p>The iterator will use <em class="parameter"><code>lock</code></em>
 to retrieve the next item of the list and it
will then call the <em class="parameter"><code>item</code></em>
 function before releasing <em class="parameter"><code>lock</code></em>
 again.</p>
<p>When a concurrent update to the list is performed, usually by <em class="parameter"><code>owner</code></em>
 while
holding <em class="parameter"><code>lock</code></em>
, <em class="parameter"><code>master_cookie</code></em>
 will be updated. The iterator implementation
will notice the update of the cookie and will return <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> to
the user of the iterator in the next call to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a>.</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="gst-iterator-new-list.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>type</p></td>
<td class="parameter_description"><p><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of elements</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>lock</p></td>
<td class="parameter_description"><p>pointer to a <a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> protecting the list.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>master_cookie</p></td>
<td class="parameter_description"><p>pointer to a guint32 that is incremented when the list
is changed.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>list</p></td>
<td class="parameter_description"><p>pointer to the list</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>owner</p></td>
<td class="parameter_description"><p>object owning the list</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>item</p></td>
<td class="parameter_description"><p>function to call on each item retrieved</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-new-list.returns"></a><h4>Returns</h4>
<p> the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> for <em class="parameter"><code>list</code></em>
.</p>
<p>MT safe.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-new-single"></a><h3>gst_iterator_new_single ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
gst_iterator_new_single (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>,
                         <em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *object</code></em>);</pre>
<p>This <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> is a convenient iterator for the common
case where a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> needs to be returned but only
a single object has to be considered. This happens often
for the <a class="link" href="GstPad.html#GstPadIterIntLinkFunction" title="GstPadIterIntLinkFunction ()"><span class="type">GstPadIterIntLinkFunction</span></a>.</p>
<div class="refsect3">
<a name="gst-iterator-new-single.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>type</p></td>
<td class="parameter_description"><p><a href="/usr/share/gtk-doc/html/gobject/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of the passed object</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>object</p></td>
<td class="parameter_description"><p>object that this iterator should return</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-new-single.returns"></a><h4>Returns</h4>
<p> the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> for <em class="parameter"><code>object</code></em>
.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-copy"></a><h3>gst_iterator_copy ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
gst_iterator_copy (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre>
<p>Copy the iterator and its state.</p>
<div class="refsect3">
<a name="gst-iterator-copy.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-copy.returns"></a><h4>Returns</h4>
<p> a new copy of <em class="parameter"><code>it</code></em>
.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-free"></a><h3>gst_iterator_free ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_iterator_free (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre>
<p>Free the iterator.</p>
<p>MT safe.</p>
<div class="refsect3">
<a name="gst-iterator-free.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to free</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-next"></a><h3>gst_iterator_next ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
gst_iterator_next (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                   <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *elem</code></em>);</pre>
<p>Get the next item from the iterator in <em class="parameter"><code>elem</code></em>
.</p>
<p>Only when this function returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-OK:CAPS"><code class="literal">GST_ITERATOR_OK</code></a>, <em class="parameter"><code>elem</code></em>
 will contain a valid
value. <em class="parameter"><code>elem</code></em>
 must have been initialized to the type of the iterator or
initialized to zeroes with <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#g-value-unset"><code class="function">g_value_unset()</code></a>. The caller is responsible for
unsetting or resetting <em class="parameter"><code>elem</code></em>
 with <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#g-value-unset"><code class="function">g_value_unset()</code></a> or <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#g-value-reset"><code class="function">g_value_reset()</code></a>
after usage.</p>
<p>When this function returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a>, no more elements can be
retrieved from <em class="parameter"><code>it</code></em>
.</p>
<p>A return value of <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> indicates that the element list was
concurrently updated. The user of <em class="parameter"><code>it</code></em>
 should call <a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()"><code class="function">gst_iterator_resync()</code></a> to
get the newly updated list.</p>
<p>A return value of <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ERROR:CAPS"><code class="literal">GST_ITERATOR_ERROR</code></a> indicates an unrecoverable fatal error.</p>
<div class="refsect3">
<a name="gst-iterator-next.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>elem</p></td>
<td class="parameter_description"><p>pointer to hold next element. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Out parameter, where caller must allocate storage."><span class="acronym">out caller-allocates</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-next.returns"></a><h4>Returns</h4>
<p> The result of the iteration. Unset <em class="parameter"><code>elem</code></em>
after usage.</p>
<p>MT safe.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-resync"></a><h3>gst_iterator_resync ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_iterator_resync (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre>
<p>Resync the iterator. this function is mostly called
after <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a> returned <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a>.</p>
<p>When an iterator was pushed on <em class="parameter"><code>it</code></em>
, it will automatically be popped again
with this function.</p>
<p>MT safe.</p>
<div class="refsect3">
<a name="gst-iterator-resync.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to resync</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-push"></a><h3>gst_iterator_push ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_iterator_push (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                   <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *other</code></em>);</pre>
<p>Pushes <em class="parameter"><code>other</code></em>
 iterator onto <em class="parameter"><code>it</code></em>
. All calls performed on <em class="parameter"><code>it</code></em>
 are
forwarded to <em class="parameter"><code>other</code></em>
. If <em class="parameter"><code>other</code></em>
 returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a>, it is
popped again and calls are handled by <em class="parameter"><code>it</code></em>
 again.</p>
<p>This function is mainly used by objects implementing the iterator
next function to recurse into substructures.</p>
<p>When <a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()"><code class="function">gst_iterator_resync()</code></a> is called on <em class="parameter"><code>it</code></em>
, <em class="parameter"><code>other</code></em>
 will automatically be
popped.</p>
<p>MT safe.</p>
<div class="refsect3">
<a name="gst-iterator-push.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to use</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>other</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to push</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-filter"></a><h3>gst_iterator_filter ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> *
gst_iterator_filter (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                     <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>,
                     <em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *user_data</code></em>);</pre>
<p>Create a new iterator from an existing iterator. The new iterator
will only return those elements that match the given compare function <em class="parameter"><code>func</code></em>
.
The first parameter that is passed to <em class="parameter"><code>func</code></em>
 is the <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> of the current
iterator element and the second parameter is <em class="parameter"><code>user_data</code></em>
. <em class="parameter"><code>func</code></em>
 should
return 0 for elements that should be included in the filtered iterator.</p>
<p>When this iterator is freed, <em class="parameter"><code>it</code></em>
 will also be freed.</p>
<div class="refsect3">
<a name="gst-iterator-filter.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to filter</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>func</p></td>
<td class="parameter_description"><p>the compare function to select elements. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>user data passed to the compare function. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-filter.returns"></a><h4>Returns</h4>
<p>a new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>.</p>
<p>MT safe. </p>
<p><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-fold"></a><h3>gst_iterator_fold ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
gst_iterator_fold (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                   <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFoldFunction" title="GstIteratorFoldFunction ()"><span class="type">GstIteratorFoldFunction</span></a> func</code></em>,
                   <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *ret</code></em>,
                   <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre>
<p>Folds <em class="parameter"><code>func</code></em>
 over the elements of <em class="parameter"><code>iter</code></em>
. That is to say, <em class="parameter"><code>func</code></em>
 will be called
as <em class="parameter"><code>func</code></em>
 (object, <em class="parameter"><code>ret</code></em>
, <em class="parameter"><code>user_data</code></em>
) for each object in <em class="parameter"><code>it</code></em>
. The normal use
of this procedure is to accumulate the results of operating on the objects in
<em class="parameter"><code>ret</code></em>
.</p>
<p>This procedure can be used (and is used internally) to implement the
<a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()"><code class="function">gst_iterator_foreach()</code></a> and <a class="link" href="gstreamer-GstIterator.html#gst-iterator-find-custom" title="gst_iterator_find_custom ()"><code class="function">gst_iterator_find_custom()</code></a> operations.</p>
<p>The fold will proceed as long as <em class="parameter"><code>func</code></em>
 returns <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a>. When the iterator has no
more arguments, <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a> will be returned. If <em class="parameter"><code>func</code></em>
 returns <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a>,
the fold will stop, and <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-OK:CAPS"><code class="literal">GST_ITERATOR_OK</code></a> will be returned. Errors or resyncs
will cause fold to return <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ERROR:CAPS"><code class="literal">GST_ITERATOR_ERROR</code></a> or <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> as
appropriate.</p>
<p>The iterator will not be freed.</p>
<div class="refsect3">
<a name="gst-iterator-fold.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to fold over</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>func</p></td>
<td class="parameter_description"><p>the fold function. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>ret</p></td>
<td class="parameter_description"><p>the seed value passed to the fold function</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>user data passed to the fold function. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-fold.returns"></a><h4>Returns</h4>
<p> A <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="type">GstIteratorResult</span></a>, as described above.</p>
<p>MT safe.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-foreach"></a><h3>gst_iterator_foreach ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a>
gst_iterator_foreach (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                      <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorForeachFunction" title="GstIteratorForeachFunction ()"><span class="type">GstIteratorForeachFunction</span></a> func</code></em>,
                      <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre>
<p>Iterate over all element of <em class="parameter"><code>it</code></em>
 and call the given function <em class="parameter"><code>func</code></em>
 for
each element.</p>
<div class="refsect3">
<a name="gst-iterator-foreach.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>func</p></td>
<td class="parameter_description"><p>the function to call for each element. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>user data passed to the function. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-foreach.returns"></a><h4>Returns</h4>
<p> the result call to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a>. The iterator will not be
freed.</p>
<p>MT safe.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-iterator-find-custom"></a><h3>gst_iterator_find_custom ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_iterator_find_custom (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>,
                          <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>,
                          <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> *elem</code></em>,
                          <em class="parameter"><code><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre>
<p>Find the first element in <em class="parameter"><code>it</code></em>
 that matches the compare function <em class="parameter"><code>func</code></em>
.
<em class="parameter"><code>func</code></em>
 should return 0 when the element is found. The first parameter
to <em class="parameter"><code>func</code></em>
 will be the current element of the iterator and the
second parameter will be <em class="parameter"><code>user_data</code></em>
.
The result will be stored in <em class="parameter"><code>elem</code></em>
 if a result is found.</p>
<p>The iterator will not be freed.</p>
<p>This function will return <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> if an error happened to the iterator
or if the element wasn't found.</p>
<div class="refsect3">
<a name="gst-iterator-find-custom.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>it</p></td>
<td class="parameter_description"><p>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>func</p></td>
<td class="parameter_description"><p>the compare function to use. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>elem</p></td>
<td class="parameter_description"><p>pointer to a <a href="/usr/share/gtk-doc/html/gobject/gobject-Generic-values.html#GValue-struct"><span class="type">GValue</span></a> where to store the result. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>user data passed to the compare function. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gst-iterator-find-custom.returns"></a><h4>Returns</h4>
<p> Returns <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the element was found, else <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a>.</p>
<p>MT safe.</p>
</div>
</div>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstIterator"></a><h3>struct GstIterator</h3>
<pre class="programlisting">struct GstIterator {
};
</pre>
<p><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> base structure. The values of this structure are
protected for subclasses, use the methods to use the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>.</p>
<div class="refsect3">
<a name="GstIterator.members"></a><h4>Members</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="300px" class="struct_members_name">
<col class="struct_members_description">
<col width="200px" class="struct_members_annotations">
</colgroup>
<tbody></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorItem"></a><h3>enum GstIteratorItem</h3>
<p>The result of a <a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a>.</p>
<div class="refsect3">
<a name="GstIteratorItem.members"></a><h4>Members</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="300px" class="enum_members_name">
<col class="enum_members_description">
<col width="200px" class="enum_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-ITEM-SKIP:CAPS"></a>GST_ITERATOR_ITEM_SKIP</p></td>
<td class="enum_member_description">
<p>Skip this item</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-ITEM-PASS:CAPS"></a>GST_ITERATOR_ITEM_PASS</p></td>
<td class="enum_member_description">
<p>Return item</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-ITEM-END:CAPS"></a>GST_ITERATOR_ITEM_END</p></td>
<td class="enum_member_description">
<p>Stop after this item.</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstIteratorResult"></a><h3>enum GstIteratorResult</h3>
<p>The result of <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a>.</p>
<div class="refsect3">
<a name="GstIteratorResult.members"></a><h4>Members</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="300px" class="enum_members_name">
<col class="enum_members_description">
<col width="200px" class="enum_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-DONE:CAPS"></a>GST_ITERATOR_DONE</p></td>
<td class="enum_member_description">
<p>No more items in the iterator</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-OK:CAPS"></a>GST_ITERATOR_OK</p></td>
<td class="enum_member_description">
<p>An item was retrieved</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-RESYNC:CAPS"></a>GST_ITERATOR_RESYNC</p></td>
<td class="enum_member_description">
<p>Datastructure changed while iterating</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-ITERATOR-ERROR:CAPS"></a>GST_ITERATOR_ERROR</p></td>
<td class="enum_member_description">
<p>An error happened</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="gstreamer-GstIterator.see-also"></a><h2>See Also</h2>
<p><a class="link" href="GstElement.html" title="GstElement"><span class="type">GstElement</span></a>, <a class="link" href="GstBin.html" title="GstBin"><span class="type">GstBin</span></a></p>
</div>
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